In a variety of applications of practical importance, environmentally sensitive circuitry included in a housing is designed to be interconnected via electrical leads to associated elements mounted on, say, a printed-circuit board. To protect the circuitry against potentially harmful factors such as moisture and dust, it is advantageous to hermetically seal the leads where they extend through openings in the housing.
Additionally, it is often important to shield the circuitry included in the housing from extraneous electromagnetic radiation in the surrounding environment, as well as to shield the environment from radiation generated by circuitry in the housing. This can be done, for example, by making the housing out of an electrically conductive material and connecting the housing to a point of reference potential.
Illustratively, an insulating material such as glass is formed around each of the electrical leads in the openings through the housing. In that way, the leads are both electrically insulated from the conductive housing and hermetically sealed with respect to the housing.
In practice, the leads that extend between the housing and the associated printed-circuit board serve in effect as antennas that pick up extraneous radiation present in the environment and/or transmit extraneous signals into the surrounding space. Signals picked up by or emanating from the leads constitute undesireable noise signals in the assembly.
Moreover, movement of the noted leads during or subsequent to manufacture of the assembly may stress and crack the aforementioned hermetic seals. In some cases, such movement of the leads may not only destroy the seals but also damage connections within the housing to which the leads extend.
Accordingly, efforts have continued by workers skilled in the art directed at trying to devise improved electronic assemblies. In particular, these efforts have been focused on attempting to provide better shielding of interconnecting leads and to minimize damage caused by movement of the leads. It was recognized that such efforts, if successful, would improve the manufacturability, reliability and operation of such assemblies.